In use, fuel nozzle sheaths are submitted to relatively severe stresses. This significantly impedes the service life of the nozzle sheaths. Stress concentration zones in the sheath may lead to sheath deformations. Large sheath deformation should be avoided to prevent load transfer from the combustion shell to the fuel nozzle stem via the nozzle sheath. Sheath deformations can also result in fretting damage on the fuel nozzle stem.
Accordingly, there is a need to provide a solution to the above mentioned problems.